[Would you like to see this in-game?]
TL;DR: A Chevy C60L with a 6-pdr plonked on the back.
The portee of guns is a very common ad hoc technique most commonly tied to the British. Initially, the portee of guns was to prevent weapons from being damaged from long-term towing across rough terrain, however, some crews tended to fire these weapons from their vehicles as the extra mobility provided by this method was rather appealing. The most common portees seen are those with the 2-pdr, however, when the first 6-pdrs started arriving, they were very quickly mounted in the same way, though these pieces were getting a bit too heavy to move from the vehicle and back again. One of the vehicles that found itself mounted with the 6-pdr, was the Chevy C60L, a 3-ton 4x4 truck with a 3-ton load capacity. Due to these capabilities, the less than two ton 6-pdr gun was no issue for the chassis. These vehicles found themselves in the hands of Australian crews as well as, potentially, the LRDG. Some were even further modified with addition plates for protection.
Place In War Thunder:
Portee guns were a large part of Britain’s North African Campaign and I believe this example to be the most fitting for the game in terms of weaponry. The 2-pdr portees would work fine, however, there are more effective and armored vehicles that already use the gun. The 6-pdr, on the other hand, only appears as low as 3.0 due to its effectiveness. Having a 3.0 gun at a 1.0~ battle-rating could be fairly enticing. It would also get newer players more accustomed to having a rear-mounted gun. This knowledge would be incredibly useful when they unlock the Archer. I feel like this vehicle would fit best as a rank I 1.0~ tech tree vehicle, ideally in the same line as the Archer. Playstyle of the machine would be rather unique as positioning would be the most difficult part, however, once in that position, anything unfortunate enough to drive into your line of fire would be quickly eliminated by the effective 6-pdr. When you’re satisfied, pack up and move to another position using your mobility.
Armament: 6-pdr gun
Dimensions: 6.20m x 2.29m x 2.79m (L,W, H) (Dimensions of the original truck. This vehicle is actually shorter.)
Armor: None. (Some were fitted with metal panels of an unknown thickness or quality.)
Crew: 4 (Driver, Co-Driver, Gunner, Loader)
Ammunition: Same as the 6-pdrs in game, however, the selection might be limited for balancing purposes.
Side View (Potentially in service with the LRDG):
Side View with added armor:
Another angle of the above vehicle:
Drawing of the vehicle from the side:
Drawing of the vehicle from the rear:
Drawing of the vehicle from the side with additional armor:
weaponsandwarfare.com - weaponsandwarfare Resources and Information.
Engines of the Western Allies in WW2
Canadian Military Pattern truck - Wikipedia
Ordnance QF 6-pounder - Wikipedia